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Experiences of federal prosecutors and investigators of sexual assault cases occurring in Indian Country
Get PDFThis thesis is a qualitative evaluation of how federal criminal justice professionals work together in the investigation and prosecution of sexual assault cases on reservations. Historically, sexual assault was one of the tactics used by European settlers to control and dominate Native Americans, and this, among other colonial processes, has resulted in historical trauma that has continued to impact tribes to this day (Smith, 2015). Today, Native American women experience sexual violence at rates higher than any other demographic (Evans-Campbell, 2008; Riley, 2016). Another effect of colonialism was the establishment of the paternalistic relationship between the U.S. government and Indian Nations that many attribute partly to the creation of the General Crimes Act in 1834 and the Major Crimes Act in 1885 (Price, 2013; Riley, 2016; Rolnick, 2016; Sands, 1998). The General Crimes Act extended federal law to Indian Country for interracial offenses, and the Major Crimes Act diminished tribal sovereignty by mandating that certain felonies committed by Indians in Indian Country were to be investigated and prosecuted federally - sexual assault being one of these crimes. Although tribal courts retain concurrent jurisdiction in these cases, the Indian Civil Rights Act and the 2013 Re-authorization of the Violence Against Women Act have restricted tribal courts, who often refer sexual assault cases to federal criminal justice officials. This makes the Federal Bureau of Investigation (FBI) and U.S. Attorneys primarily responsible for the investigation and prosecution of sexual assault occurring in Indian Country. This research aimed to understand the experiences of some of these federal criminal justice officials in the investigation and prosecution of sexual assault cases occurring in Indian Country. The findings of this research suggest a need for cultural and educational training to be required of federal criminal justice personnel who will be working in Indian Country, and they also question the necessity of federal criminal justice involvement in sexual assault cases occurring in Indian Country
Climatic memory of tree growth in the southwestern US
No full textThe controls on forest carbon cycling are the focus of much interest, as forests store nearly half of terrestrial carbon, can exhibit large temporal variability in flux rates, and will undergo significant stresses, and likely state shifts under climate change. Towards this, a large body of research on the mechanisms and controls on tree mortality from drought has given us insight into the physiological processes taking place in dying or declining trees. Despite this, understanding of the processes controlling tree growth, including the temporal and spatial variability among different species could be improved, particularly in the southwestern US (“Southwest”), where tree growth is quite variable. This dissertation addresses three broad weaknesses in current understanding of the climatic controls on tree growth in the Southwest. In particular, understanding of the physiological processes occurring in trees surviving drought, particularly in the years that follow droughts stress, is a key weakness in current knowledge. Second, understanding of the importance of antecedent climate, that is, conditions occurring multiple years before ring formation, for tree growth is also limited. Third, time-invariant approaches to modelling growth are likely insufficient to capture the variability in tree growth responses to climate, and recognition of plasticity in growth-climate responses and their temporal characteristics is likely needed. I review some of these limitation in chapter 1. In chapter 2, I quantify the legacy effects of drought across 10 species using a temporally correlated mixed effects model. I document long and complex legacies in tree growth-climate sensitivities (recovery times often ~ 5 years) and important species differences. Given this lagged importance of drought, in chapter 3 I apply a more temporally flexible stochastic antecedent model (SAM) to tree-ring chronologies to show that more than 50% of growth-drought sensitivities are driven by conditions occurring more than 2 years prior to ring formation, and that growth sensitivities vary strongly across the region, likely related to the North American Monsoon gradient. In chapter 4, I expand the SAM approach applied in chapter 3 to account for variation in growth-climate relationships related to La Niña years (dry winters) and their legacies, and show that both these relationships and their temporal characteristics (“memory”) are plastic. Taken together, the results from this dissertation call for a need to include more complex temporal variability in growth into predictive models. These results also demonstrate a continuing need for experiments to identify the mechanisms underlying drought legacy effects and complex tree growth patterns, with a focus on understanding the role of non-structural carbohydrates in driving variability in tree growth through time and space
Effects of acute noise exposure on DNA damage response genes in the cochlea, cortex, heart and liver
No full textBackground: Noise as a systemic stressor induces various organ dysfunctions and the underlying molecular pathology is unknown. However, noise exposure results in the accumulation of DNA damage in auditory and non-auditory organs, which implicates molecular mechanisms of DNA damage and repair. The DNA damage response (DDR) is a global protective mechanism that plays a critical role in maintaining DNA integrity. Previous research has revealed that chronic noise exposure alters the normal expression pattern of DDR genes in the auditory system and this alteration is associated with permanent sensorineural hearing loss.
Hypothesis: The role of DDR genes in noise induced systemic (non-auditory) pathology has not been investigated. For instance, it is known that noise exposure results in the accumulation of damaged DNA within the cortex, heart and liver, yet it is not known whether or not DDR genes are mobilized within these organs due to noise exposure. The current pilot study was designed to test the hypothesis that an acute noise exposure would alter the normal expression of DDR genes (e.g., ATM, p53 & XPC) in auditory (cochlea) and non-auditory organs, such as the cortex, heart and liver.
Methods: Mice were used as subjects in this study and consisted of a baseline group, a one hour noise exposure group, and a four hour noise exposure group. Each group of mice were sacrificed for organ harvest at each of the three time points. The organs consisted of cochlea, cortex, heart and liver. Purification and quantification of total RNA was conducted from each organ. Messenger RNA was reverse transcribed to cDNA. The cDNA products were quantified and served as templates for end-point polymerase chain reactions (PCR). These PCR products were then loaded onto 1.5% agarose for gel electrophoresis. The electrophoresis bands were then processed for semi-quantification and statistical analysis.
Results: Acute noise exposure failed to elicit statistically significant changes in DDR genes (relative to baseline) across the various organs.
Conclusions: The failure of the cochlea, heart, cortex and liver to upregulate protective DDR genes during acute noise exposure might help to explain their susceptibility to noise-induced DNA damage. This suggest that, biomedical interventions to upregulate DDR genes may need to be implemented before noise exposure or during the early stages of noise exposure
Analysis of factors affecting the frequency and severity of freight-involved and non-freight crashes on a major freight corridor freeway
Get PDFTraffic crashes cost society billions of dollars each year as a result of property damage, injuries, and fatalities. Additionally, traffic crashes have a negative impact on mobility, as they are a primary cause of non-recurring delay. With the Interstate 10 corridor between the ports of Los Angeles and Houston being one of the most vital links for goods movement across the United States, safety and mobility along this freeway, particularly for freight traffic, are of significant concern. This study, which utilized six years of crash data from the state of Arizona, explores factors affecting the frequency and severity of crashes along the Arizona portion of the I-10 corridor, with a particular focus on freight-related crashes. The safety performance along the I-10 is analyzed through the development of crash frequency and severity prediction models using integrated crash, roadway, traffic, and environmental data. Negative binomial and ordered logit models, with the incorporation of random parameters, were estimated to provide a detailed understanding of factors associated with freight-involved crashes and how they compare to non-freight crashes in terms of frequency and severity. The results showed that several roadway- crash-, vehicle-, and person-related variables were associated with the frequency and/or severity of crashes along the study corridor. These findings provide important insights which can be used to develop or plan countermeasures aimed at improving the safety and efficiency of freight travel. Additionally, during several stakeholder meetings it was determined that insufficient truck parking is becoming a serious issue for road users in the state of Arizona and throughout the country. Therefore, further analysis was completed to better understand the safety effects of parked freight vehicles near highways in the state of Arizona. The results concluded that there were not enough recorded collisions with parked vehicles in the past six years to create accurate statistical models, however, some assumptions about, location, time of day, and collision manner can be made by considering the summary statistics of those crashes. Finally, this study concludes with a brief look at emerging ITS technologies that may serve as effective countermeasures to some of the safety concerns discussed within the frequency, severity, and parked vehicle analyses
Student standardized test scores as an effective measure of teacher performance: teacher and administrator attitudes
Get PDFIn recent years, the focus of accountability has emphasized standardized test results and the individual teacher. Weight has increasingly been given to the use of standardized test results as an important tool to measure teacher effectiveness and has been implemented in a number of states through legislation that mandates its use on evaluation instruments. The emergence of Value-added Measures and Student Growth Percentiles as viable tools to accomplish the task of measuring teacher effectiveness using standardized test scores has become more prominent across school districts in the United States. However, much of the research on these tools has shown that they may not be stable enough to use in an evaluation. Additionally, the relative instability of these measures creates a larger concern when used in teacher evaluations because the results of evaluations can influence decision-making around teacher tenure, dismissal and even compensation. Using an unproven method to make these types of decisions is wrought with potential concerns about the issue of measuring teacher effectiveness.
This study served to describe the attitudes of high school mathematics teachers and high school administrators regarding the use of standardized test results on teacher evaluations. The researcher administered quantitative surveys and qualitative interviews for the purpose of better describing teacher and administrator attitudes. Both quantitative survey results and qualitative interview results were analyzed in order to better understand teacher and administrator attitudes toward the use of student standardized tests results as an indicator of performance on teacher evaluations. When describing teacher attitudes, three groups of mathematics teachers served as a valuable source of data. Groups consisted of teachers of accelerated courses only, non-accelerated only, and those that instructed both accelerated and non-accelerated courses as a part of their teaching assignment. Administrator and teacher attitudes were also analyzed in order to compare the two groups. Each group responded to the same survey items and statistical analysis was applied for the purpose of comparing the two groups. The research design was mixed methods where sequential timing was applied as a subset methodology design in order to gather survey data first and then interview data.
Survey and interview questions were categorized into three themes as related to teacher evaluation. Theme one considered the concept of standardized test results as an indicator used to measure teacher performance and/or effectiveness. Theme two questions focused on attitudes towards standardized test results and the degree of trust that participants had/did not have with regard to standardized test results. Theme three questions considered the actual process of teacher evaluations within the organization. The findings suggest that a clear attitude of disagreement exists for each group regarding theme one questions. However, the accelerated and combined (accelerated/non-accelerated) groups expressed disagreement toward theme two while the non-accelerated group was more neutral. Theme three produced similar neutral and agree responses across the three groups of teachers. Administrators also expressed an attitude of disagreement towards theme one, but were more neutral in responses to themes two and three. The idea of using standardized test results as a tool to evaluate teacher performance was met with disagreement for both teachers and administrators
Three-component hydrograph separation for the glaciated Lake Peters catchment, Arctic Alaska
No full textArctic lakes and rivers are fed by a variety of sources, including rain, snow, glacial melt, and groundwater. Due to sustained Northern Hemisphere warming associated with industrial- era atmospheric greenhouse gases, those water sources are undergoing rapid changes. However, there are relatively few studies quantifying the hydrological components of Arctic Alaskan watersheds. To estimate water source contributions in an Arctic Alaskan catchment, I conducted three years of hydrological and climatological monitoring in the glaciated Lake Peters watershed in the northeastern Brooks Range. Lake Peter’s two main inflows, Carnivore Creek and Chamberlin Creek, provide a useful comparison of catchment size, glacial coverage, surficial materials and slope. The Chamberlin watershed is small, steep, rocky, and heavily glaciated (8.1 km2, 25.9% glaciated) whereas the Carnivore watershed is larger and less glaciated (128.9 km2, 9.5%) and its channel flows through a wider and less steep valley bottom.
Weather stations continuously recorded precipitation and temperature from May 2015 to August 2017, and Chamberlin and Carnivore Creeks were monitored from May through August of 2015, 2016 and 2017 to produce high-resolution discharge and conductivity records. The two streams were sampled intermittently, and source water samples were collected in the form of rain, snow, glacial ice and melt. Water samples (n = 187) were analyzed for stable oxygen isotopes, which were used in conjunction with conductivity as tracers for a three-component hydrograph separation. The three discharge components are defined as rainfall runoff (rainwater from recent summer storms), snowmelt (melting snowpack from within previous year), and an "old water" component (water residing in the catchment for longer than one year regardless of original source, including soil water, groundwater, and glacial melt).
Carnivore Creek’s average discharge was an order of magnitude greater than Chamberlin Creek’s, at 9.4 and 0.7 m3/s respectively. Divided by catchment area, Chamberlin Creek’s specific discharge (1892 mm) was considerably larger than Carnivore Creek’s (1524 mm) for the three summers combined. Broad year-to-year similarities between the two rivers include a high responsivity to rain storms, a strong diurnal cycle, and an overall pattern of low discharge from May to mid-June increasing to peak flows in July and August. Differences between the two creeks are accentuated by higher temperatures. The two hydrographs are most similar in the coolest summer (2015) and diverge most during the warmest summer (2017), when Carnivore Creek recorded its lowest total discharge and Chamberlin Creek recorded its highest. This is attributed to Chamberlin Creek’s larger glacier coverage.
The mixing model results show that, averaged over the three-summer study period, Chamberlin Creek is 43 ± 12% rainfall runoff, 26 ± 8% snowmelt, and 31 ± 19% old water, whereas Carnivore Creek is 38 ± 8% rainfall runoff, 19 ± 8% snowmelt, and 43 ± 13% old water. The percentages of each component vary from year to year, and by day of year (DOY). The proportion of old water in Carnivore Creek correlates positively with DOY (r = 0.48, p < 0.001), and snowmelt correlates negatively (r = −0.73, p < 0.001). There is no relation between DOY and rainfall runoff in Carnivore Creek, but Chamberlin Creek’s rainfall runoff increases linearly through the summer (r = 0.58, p < 0.001). Chamberlin Creek’s old water and snowmelt have nonlinear relations with DOY best described using second-order polynomial equations. The snowmelt component has a concave-downward trend (r = −0.78, p < 0.001), starting the summer with less than 15%, peaking at 42% in the mid-summer, then lowering to around 20% in August. Inversely, the old water component has a concave-upward trend (r = 0.79, p < 0.001), with peaks of 50−70% at the beginning and end of the summers, and lows of 10% in the mid- summer.
Each modeled discharge component is compared with an independent observation of its associated water source. Cumulative summer rainfall is extrapolated from three weather stations along an elevational gradient throughout the catchment. Snowpack and glacier elevation changes are calculated by airborne photogrammetry, then converted to water equivalence (w.e.) using measured snow density (0.33 g/cm3) and known density of glacial ice (0.917 g/cm3). The rainfall observations are greater than, or within uncertainty of, the modeled rainfall discharge component for both rivers for all three summers. The snowpack w.e. observations also exceed their associated modeled discharge components for Carnivore Creek in 2015 and 2017, and Chamberlin Creek in 2015. For the other years, snowpack w.e. observations underestimate the modeled snowmelt by half.
This study does not distinguish between glacier melt and subsurface flow in the old water component, because the isotopic composition of the two is indistinguishable. An additional tracer value is required to chemically differentiate glacial melt from subsurface flow. The old water percentage increased from the beginning to end of the summer and the highest proportion of glacier melt occurred during the warmest summer. With the seasonal increase in old water discharge being attributable to glacial melt, it is clear that the glaciers are a key source of water storage throughout warm and dry parts of the summer. If glacier contribution ceases completely, total discharge could be reduced by half. Combined with the documented mass loss of glaciers throughout the Arctic, these findings emphasize the need for further hydrology research
Finite Difference Methods for the p-Laplacian
No full textThe p-Laplacian is a non-linear, differential operator whose eigenvalues and eigenfunctions have been studied for many decades. On domains in , they are well known and can be easily computed. For domains in , its spectra has been partially characterized but it is unkown if this characterization is exhaustive. Because of its challenging numerical properties, many different methods have been proposed for computing its eigenvalues and eigenvectors. We propose a new approach based on two step finite difference methods that compliments existing approaches and may be able to find eigenvalues and eigenvectors that previous approaches could not
Tex Has Horses and Plenty of Air
Get PDFTex Has Horses and Plenty of Air is a selection of a larger work of memoir, based on my experience on the Camino de Santiago in the fall of 2011. Making up approximately the first half of the memoir, these chapters track the narrator from his arrival in Paris, across the French Pyrenees and west though northern Spain. As the narrator navigates internal and external challenges, driven by his need to rid himself of a panic disorder, he questions the relationship between actual identity and performance. To distance himself from his panic, his problems, his past and present, the narrator invents a series of new identities to try out along the busy pilgrimage route and in the process comes to appreciate his experience and the anxiety he carries.
The earliest version of this memoir took shape in 2012, shortly after I returned to the US. It then continued to crop up here and there, in disjointed flashes and drafts, for the next five years. Finally, after two years in the MFA program writing almost exclusively memoir, in August of 2017, I decided to shelve the thesis I’d written about my teenage misadventures and focus instead on putting together a definitive, novel-length Camino saga. I’m relieved and pleased things took this turn. Spain was a far nicer place to revisit than R. L. Paschal High School.
The trick with committing those blurry months of wandering to paper was finding ways to integrate what I’d learned about fiction in the program— the necessary beats, the classic archetypes, the shifting fortunes— with my actual experiences. Through revision, stakes had to be emphasized and characters needed further explanation. A phrase I heard in my first workshop that I’ve held onto since suggests itself: “the truth is never enough”. The greatest challenge of this project was attempting to integrate the expectations of a novel-reader with those of a memoir-reader, making a true account come to life like fiction. This can be especially difficult when dealing with innately repetitive subject matter, like relationship dysfunction and panic attacks. As a result, this project proved an essential bit of practice in finding creative ways to maintain momentum through a series of seemingly similar crises.
I am highly influenced (though no longer quite consciously) by the works of Hemingway, as is made pretty obvious in the text. Though his terse, matter-of-fact style jars somewhat with my slightly headier, Dickensian clause-stacking, his talent for effective simplicity, for summing up people and places in single sentences, has always impressed me. On top of that, there’s always a little Wodehouse in my writing, regardless of subject matter. Funny things could be funnier and serious things need that relief, those moments of absurdity.
As a memoir, this piece is built on truth. Like most truths, it’s been slightly rearranged.
This project has allowed me to relive what was one of the most important, challenging, and rewarding experiences of my life. That alone was enough fun, for me, to justify the effort. I hope I have been successful in capturing that moment in time, that journey, in pushing past the travelogue to something more immersive. I hope I have managed to reproduce a fraction of the mad whirl of faces, conversations, highs, lows, cities and villages I found along the Way
The impact of charter school growth on segregation, funding, and academic achievement in Maricopa County
No full textIn 1994 Arizona approved Revised Statute §15-181 sometimes referred to as “charter law”. This statute was designed to perform two specific functions; the first was to increase choice for Arizona families; and the second was to increase pupil achievement. Over 20 years later, charter schools in Arizona have grown to a total of over 547 schools serving in excess of 180,000 students. This makes the percentage of students receiving their education from charter schools in Arizona one of the largest in the nation at nearly one of every five students. However, ASRS 15-181 is also one of the most lax statues in the country leaving the public education system in Arizona vulnerable to unintended consequences of the charter/choice movement.
The researcher determined the impact of charter school choice on the state’s public school system. To evaluate the impact of school choice, this study looked at how market competition and school effectiveness theories have changed the landscape of public schools. Using records from the Department of Education and the annual Superintendent’s reports, the researcher looked at enrollment and financing trends with charters and traditional public schools to measure how they were working with or against each other. The researcher also analyzed the yearly state testing results and A-F grades given to all public schools based on state standardized testing to determine differences in academic performance of charter schools versus traditional public schools.
The results of this study indicated that the evolution of charter schools in Arizona has resulted in unintended consequences to the segregation of students and the education budget while failing to yield significant academic differences. Charters have aided in demographic shifts in schools creating higher concentrations of Caucasian and Asian students in charter schools when comparing them to their traditional district school counterparts. Further, the location of new charter schools has shifted over the last twenty years away from areas with greater diversity and concentrated in areas of higher socioeconomic status and lower minority status. The impact on the public education system has been a larger financial strain on Arizona’s budget because the funding model was created prior to the use of charters as a public school option. All the while, charter schools have failed to yield academic results that vary significantly from those of nearby traditional district schools
The role of titin in contraction of skeletal muscle
No full textThe physiology of muscle contraction is commonly regarded as a mature field in which the fundamental principles, comprising the sliding-filament and swinging cross-bridge theories, have been adequately described. However, our current ability to predict in vivo muscle forces in humans and other animals is inadequate, indicating that our current model of muscle function is incomplete. Muscle proteins that were discovered after the establishment of these original theories were not incorporated into the early iterations of muscle theory. One such protein, titin, was discovered 20 years after muscle theory was codified, and its role in muscle function is still unclear. Titin spans the half-sarcomere, but is often studied in the I-band, where it is elastic and attaches the thick and thin filaments. Initial investigations suggested that titin was too compliant to contribute force during contraction. Recent studies, however, indicate that titin in skeletal muscle increases stiffness upon muscle activation. This “titin activation” theoretically improves our ability to predict in vivo muscle forces in computational models and thus has the potential to radically change our understanding of muscle contraction. Unfortunately, there is very little experimental evidence to complement these theoretical models. To experimentally explore the role of titin, I used muscular dystrophy with myositis (mdm) mice, which have a small deletion in titin that leads to a loss of titin activation, and compared contractile properties between mdm and wild-type muscles. The focus of this dissertation is to investigate the role of titin activation during two contraction modes: 1) cyclical contractions that produce negative work, and 2) isometric contractions at maximal and submaximal activation levels. These data show that muscle function is negatively affected by the mdm mutation, suggesting that this small deletion in titin, and subsequent loss of titin activation, plays a critical role in regulating force during contraction. Future studies will be required to identify the mechanisms by which titin activation regulates force during contraction, as well as the mechanisms that lead to an increase in titin stiffness in skeletal muscle